The key material, in particular the nonce/IV, is derived differently and
the IV is also generated in a different way. Additionally, the actual
content type is encrypted and there may be optional padding to mask the
actual size of the encrypted data.
To better separate the code path for different TLS versions and modes of
operation, we introduce a TLS AEAD abstraction. We provide three implementations
using traditional transforms, and get prepared for TLS AEAD modes.
Tobias Brunner